Comparison Between 3D Printing and CNC Machining
Manufacturing processes can be broadly divided into two categories: subtractive and additive. In subtractive manufacturing, the material is removed from a larger piece to create the desired shape. This is done in machining, where the cutting tool moves relative to the workpiece. The most common type of machining is milling, which involves removing material by rotating a cutter about its axis of rotation.
In additive manufacturing, the material is added together to form the desired object. This is done using 3D printing or stereolithography (SLA), where a UV laser cures liquid resin layer-by-layer to form the object. 3D printing has become increasingly popular in recent years due to its low cost and ease of use. However, there are some drawbacks compared to traditional machining techniques. In this blog post, we will compare and contrast 3D printing and CNC machining, highlighting the pros and cons of each process.
Introduction to CNC Machining
Let's delve deeper into CNC first. CNC stands for Computer Numerical Control. These machines are used to transform blocks or rods of material into net shape through coded, programmed instruction. As compared to 3D Printing, CNC machining is an old process. With time, CNC machining has evolved to meet the changing demands of the industry. CNC machines have transformed to achieve minute tolerances as well as smooth surfaces.
A manual operator is not required to control CNC Machining directly. This process is needed to take care of low to mid volumes of composites or plastics. CNC machining helps give metals, ceramics, and even wood the required shape. It is known for its accuracy as well as precision. However, CNC machining has one drawback. It has a tendency of material wastage.
The process of CNC machining is utilized for the production of finished parts. The method is employed in industries where the process is repeatable, like medical, oil & gas, electronics, aerospace, and transportation. Different types of CNC machines are used for polymers and composites. The machining operation is chosen depending on the material. For instance, milling machines, lathes and turning machines, laser machines, etc.
Introduction to 3D Printing
As opposed to CNC machining, 3D printing is used for creating prototypes and models. However, recently it is even being used to create final products. 3D printing is used for manufacturing furniture, tools, tripods, gifts, etc. With the advent of technology, it has become easy to hire freelancers for 3D printing as well. Using 3D modeling software and a 3D printer, a freelance 3D printing expert produces solid three-dimensional items. 3D printing is a relatively new technology. More people and businesses are discovering methods to use 3D printers for object design and printing.
Demand for 3D printing freelancer specialists who can utilize their imagination and technical know-how to design products based on client specifications using 3D modeling software will increase as the technique becomes more widespread.
To successfully deliver printed things to clients, a freelance 3D printing expert must have knowledge in all design and production stages. Moreover, it is even utilized to create wax casting for making jewelry. Automotive industries use 3D printing to manufacture parts. Aviation industries, archaeologists, paleontologists, physicians, medical technicians, and even students use 3D printing to create simple to complicated projects.
Difference Between 3D Printing and CNC Machining
Although manufacturers have made both processes standard, each process has evolved to meet the industry's specific demands. This makes it important to understand both the methods, the objectives they meet, their capabilities and differences, and the applications - CNC Machining vis-a-vis 3D Printing.
Processes: Additive vs. Subtractive
CNC routing and 3D printing have major differences in processes. The procedures they follow are completely opposite. CNC machining functions by taking a material mass and then subtracting from it to create unique parts. However, 3D printing functions by building materials from scratch. CNC routers function based on computer-aided design software or CAD software. The software creates a blueprint of the specific part. It then proceeds to make the part through computer-aided manufacturing software or CAM software for cutting a part of the material. In simple terms, this method is subtractive as it extracts a part - the finished work is a refined part. The finished work has fewer materials as compared to the previous state.
In contrast, 3D printing takes the opposite route. While 3D printing uses CAD and CAM software like CNC machining, the process here is to create products by following an additive process. CNC machining begins with more materials and reduces to the final product stage. And 3D printing manufactures parts by following a process wherein layers of materials are added successively using the software. The 3D file source needs to be sliced into multiple layers wherein every layer generates a set of instructions controlled by the computer.
Specialization: Rapid Prototyping vs. Mass Production
CNC machining has evolved over the years. However, 3D printing is a relatively new process. It has not been utilized completely yet. Hence, industries are still exploring the capabilities of 3D printing. While both 3D printing and CNC routers do almost the same type of things, they meet different objectives and are required for various purposes.
CNC routers are an important industrial tool, specifically meeting the demands of large-scale industries and mass production. These machines can manufacture large products required for high-tech machinery with ease and efficiency. On the other hand, 3D printers are suitable for creative, medical, and domestic purposes. 3D printing is perfect for rapid prototyping.
3D printing is more suitable for individually manufactured products. As they do not offer the benefit of scalability for producing goods in large quantities, they are best suited for industries with customized consumers. The objective is to provide consumers with things that they require in the desired forms. 3D printing can create minute industrial parts. However, it is not able to produce it in mass. Creators are using this process for developing unique customized gifts, pieces of art, and the like.
Usage: Heavy material vs. Light Material
Industries in the area of automotive, aerospace, and the likes are heavily dependent on CNC machining. This is because CNC routers help produce heavy material with exact precision. In opposition to this, 3D printing has great limitations when creating parts with different materials or manufacturing layers with denser materials. 3D printing uses the additive layering process, which is yet to develop and advance.
CNC routers are blessed with heat management systems and robust servo mechanisms. They are built to take care of heavier metals and materials, which is not possible with 3D printers. 3D printing cannot be used for making materials that need more than one type of material for its manufacturing. 3D printing can be utilized for prototyping plastic materials. Yet, its efficiency in creating denser metals or heavier materials is not fully explored.
CNC machining is ideal for manufacturing precision parts that are perfect for engines, machinery, airplanes, vehicles, and other such areas. Further, CNC can even be used for wood, plastic, wax, and many other materials. 3D printing uses unique materials for the process. Hence, they do not have the required strength to use it for heavy materials or areas like airplanes and vehicles. It is used for specialized functions like resins, metals, plastic, and the like.
This makes 3D technology more suitable for manufacturing models for prototypes in addition to products for domestic purposes and individual use. CNC machining is preferable for many purposes that are still not explored by 3D printing.
Sizes: Small Products vs. Large Products
CNC routers have proficiency in scaling between different sizes, from large to small products. The scale produced by the CNC router depends on the machine's capability and the raw material used in the production. 3D printers use an additive process that prevents them from generating large-sized products.
3D printing also takes much longer to produce larger items at this stage. The layering process used by 3D printing is not suitable for creating extensive articles. And here it is where CNC routers play an important role. 3D printing is suitable for composing simple and small designs. CNC machining is a powerful industrial tool that can create bulky parts efficiently.
While the three-dimensional printing process cannot create large products of this size, experts are of the opinion that this process is still in its nascent stage of development. The future holds great possibilities for 3D printing. It is evolving and soon might be capable of producing bigger items.
Precision: Small Products vs. Large Products
There is a stark difference between the two processes. They have different tolerance sensitivities and even quality. CNC machining is known to offer excellent surface quality. 3D printing is yet to evolve to be used in critical applications. 3D printing has been breaking new ground by entering smaller markets. With a range of customized items for individual and domestic use, 3D printing has become the industry's favorite.
3D printing makes use of Selective Laser Melting technology. Yet it cannot replicate the precision and accuracy of the CNC machining process. Herein 3D printing is somewhat less efficient as compared to robust CNC machining. The former lacks precision, which is the forte of the latter. For example, while the CNC milling process can offer an accuracy of 1 mm on each axis, this precision is not possible with 3D equipment.
Parts produced by CNC machining are ready to be used, while the 3D printing process, at times, requires specialized steps to finish the task. Products created through 3D printing require hand finishing vis-a-vis CNC machining. The element of refinement gets missed by 3D print technology. CNC router is known for high tolerance to create accurate products that are high in detail.
Conclusion
While both the processes have some similarities, the purposes, capacities to produce, the load they can handle, and the size of the products, along with refinement capabilities between two, are very different. However, CNC machining and 3D printing can work together to produce complicated parts rapidly.
Author Bio
Sakshi Baid works as a Product Associate at Refrens.com - Online Invoice Generator & India's most powerful platform for freelancer growth. She has worked as a Brand and Digital marketing associate for some renowned companies.
Enjoy powerful modeling, rendering, and 3D printing tools without the steep learning curve.
.png)
Need to learn 3D modeling? Get started with interactive tutorials.